Hello Viessmann-Community,
my grandfather has had a problem with his Viessmann “Trimatik-P (order no. 7410 061-A)” heating system for some time. The control unit does not switch on the circulation pump in day mode after about 45 minutes as usual, but sometimes takes 4 to 5 hours after the boiler temperature has been reached. A problem with the control unit is ruled out, as he has already purchased three control units of this type and the same error still occurs. The control of the circulation pump itself works when the chimney sweep test socket on the side is actuated. Unfortunately, local heating mechanics cannot find a fault and are not "Viessmann"-experts. Can anyone help me with this so that I can help my grandpa? If there are any farer information needed, please let me know.
Many thanks in advance! 🙂
